Adjustable combustion-controlling apparatus



March 26, 1929. L, oE -r 1,707,012

ADJUSTABLE COMBUSTION CONTROLLING APPARATUS Filed Feb. 5, 192a gwuwtoz Patented Mar. 26, 1929.

LOUIS HOEDT, or nnooxn n, new YORK.

ADJUSTABLE CQMBUSTION-CONTROLLING APPARATUS.

Application filed February The invention relates to combustion controlling apparatus for furnaces, more particularly of the household type such as the ordinary steam boiler furnace in common use-although with certain modifications of the heating system the novel control may be applied equally well to hot waterheating apparatus; and comprises a supplementary regulating attachment therefor.

The invention is adapted especially to heating apparatus in which there is employed a forced draft for the fire; and it has for its object to accelerate the cut-off action of the usual regulator employed, as the pressure controlled diaphragm apparatus of a boiler, for example, thus equipped for forced draft combustion, and to check for a predetermined and adjustable period throwing into operation again the draft producing apparatus, so that overheating by said furnace will be avoided and economy in fuel con sumption effected. i

A further object of the invention resides in certain details of construction ofthe novel regulator apparatus whereby it is not ontirely dependent on theexisting boiler pressure or the like, but itsreturn'to position for throwing into action the forced draft mechanisni may be damped or caused to lag more or less behind the movement of the usual regulator in order that a better and more economical temperature regulation is attainable, the changes not being very marked from the particular point to which the governing apparatus has been set. The invention contemplates, also, adjustable means which may readily be set for maintaining predetermined temperature conditions.

By thus affording a very close regulation of the furnace operation, it is possible to in.-

stali a forced draft mechanism with house i hold types of boilers and permit thereby of the utilization of cheaper grades of coal, such as No. 2 buckwheat or rice sizes and mixtures thereof.

In the accompanying drawings which il-i lustrate the invention.

Fig. 1 shows in side elevation the novel regulator attachment associated, for example, with a steam boiler and blowerapparatus forthe furnace thereof, said attachment being indicated as controlling the operation of the forced draft mechanism. a

E2, is detail fragmentary ltifrjigitmlinal 3, 1928. ScIiaINO. 251,514.

section of the novel governing member employed, and Fig. 3 is a plan thereof.

Fig. 4 is a fragmentary sectional view illustrating the conditions prevailing in the governing member in one of its extreme positions. a

Fig. 5 is a detail f'agmentary elevation of the adjustable connection between the power switch and the regulating mechanism.

Referring to the drawings, 10 designates a steam boiler of the ordinaryhousehold type but in connection with which there has been installed a blower 11 for introducing air under pressure into the sealed ash pit 12 of the furnace. The said blower is to be driven by an electric motor 18 to which power is suppliedby leads 14 from switch mechanism of any well-known standard or special type inclosed in a suitable switch box 15, and to which mechanism are connected the power mains 16.

This switch mechanism, furthermore, is designed to be controlled from the novel regulator device hereinafter set forth as through an extension or arcuate arm 17 attached thereto and having a longitudinal slot 18 therein .into which fits one end of a connecting link 19. Moreover, the said end of the latter, through a roller 19, slides in the arcuate slot 18 of the arm; and over the said arm, in turn, is arranged to be moved for adjustment a stop member 20 having a spring-pressed detent 21 to hold said stop at various points along the arm through engagement with the toothed upper edge thereof. Corresponding graduations 22 are provided beneath the same along the face of the arm, so that the extent of travel of the end of link 19 may be set to obtain different temperature conditions conforming to the graduations.

The opposite end of the said link is pivotally connected to the longer arm of the oscillatable controllingbar 25 of the usual pressure controlled diaphragm regulator 26 associated wit-h steam boilers and the like.

Rigidly supported at the requsite angle on said bar 25, by a pair of straps 27 or the like extending therefrom on the switch 1 side of said diaphragm regulator, is a control member containing a suitable liquid preferably a light oil or glycerine. This control member comprises two boxes: or eranpartmers and as at 5*itliisl itlltially equal and comparatively large capacity and connected by a tube-30 of reduced cros sect onal; area, the connecting tube prefer ably being. square 11 1 cross-section, and the compartments constructed as squarciboxes,

The box 29, moreover, is at a lower level.

' than the box 28, thetopof theformer being substantially online with the bot-ton of the latter; and an air connection 31 is provided between the two said boxes and having also vent openings 32 along its underside so that flow between said two boxes may be 'freeexcept as'regulated in manner hereinafter described A partition wall 33 extends across the upper end of thetube 30, toa short"distance-below thetop of thesame,

" "leaving, however, an appreciable opening 3sttherea't so thatfluid, in passing from the box 29 to.the"box 28- maybe rapidly discharged into the-latter through said opening. In the IQVGISG"(lllOCClOIl, however, the return flow. is'imped'e'd or restricted to-that passing through a small opening 34 cont-rolled by m'eans ot'an adjustable needle valve 35, the return-of fluid-from box 28 to box 29 being all? through said valve-controlled-opening,

I and a' splash plateor bafil'e'member 36 being provided to this endwithin box 28*acr0ss the; same at the opening 34" so as to check return thr ough this opening and prevent any possible splashing of liquid into the vent connection 31.

Asheieinbetore stated, the novel regular tor-or c'ontrolmember'is rigidly connected to the controlling bar- 25- which, through the operating bell-crank37 of the pressure controlled 'diaphr-agm regulator, is oscillatable about-the, fulcrum 38. and willithus, impart similar movement to the control member; Thus, due to the rise and fall of the bellcrank- 37 jot-"the diaphragm regulator under the dilf'erent thermic conditions, the control thecircuit to the motor. This brings about Y an increase of temperature, bell-crank 37 then gradually rising and lifting with it the control" member to the horizontal, position indicated in tulllines and to a point beyond the same where the level. of, the box 28 is somewhat below. that of the box 29, where upon, as the member-becomes overbalanced, a rapid-delivery. of the liquid fromthe latter into the former through'the opening 34 will take place and cause a suddenlifting of the controlling bar 25 to the upper of the two positions indicated in dotted lines. This also swings with it the arm 17 to break the circuit at the switch 15 and shut off the blower.

The time required. for this operation depends upon the amount of liquid in the contamer-29:15 wellas area of the opening Ill and is initially determined to suit the desired conditions; The amount of liquid and capacity of the compm'tmcnts, however, should not be such that the liquid will rise appreciably abm'e the level indicated in Fig. t; that is to say, be somewhat below the bafile 36 when compartment 28 is in its extreme lowered position shown. A snap switch action is also thereby attained as the final overbalancingtakes place suddenly.

Thereupon, the bell-crank begins to dro) gradually, bar 25 following, the bell-cram actuating member 39 until the lower end ofthe link 19 sliding through the slot 18 contacts through its roller 19 with the stop 20. This will introduce sullicient resistance toprevent further downward movement of said control member and; the bar 25 to which it is attached; but asthe control member is then substantially in the horizontal position indicated in full? lines, the liquid from box 28will' return to the box 29 but only slowly and as determined-by the opcningil l", which thus affords a meansfor regulating the time for again introducing the forced draftto the furnace throughoperation of the blower 11'. \Vhen substantially all of theliquid has returned to t'lie'box 29, there will" be sufficient weight exerted on bar 2!) to force downwardly the arm 17 to the lowermost position, show-n-in-dotted lines, in-which the switch is again closed and the cycle of operation is repeated.

g It will be noted that the short leverage on thebox- 28 side and the fact that the liquid inthis compartment overbalunces the appn ra-tus,-makesit impossible to actuate the switch member 15 to close the motor circuit until such time as appreciable liquid in the said compartment has percolatcd through the needle valve controlled opening to the con'ipartment 29, when-the snap actii'm again oecursto close-theswitch. A considerable range, sayfrom-one minute to one hour, is thereby afforded in the restoration of the blowing operation which, it will be approciated, makes foreconomical operation of the furnace.

'A further regulation. as well as adjustment in the installation of the controlling apparatus is afforded by-thc setting of the stop member 20'alonga small length of the innerend ofv the arm'l7, it being apprcciatedthat' the longer the leverage atiorded at thisarm the less effort will be, re uired to trip the switch and consequently ess time required for sufilcicnt liquid to flow from the compartment 28 to the compartment 29 for this purpose.

The present application is a continuation in part of the previous application filed by me April 21, 1927, Serial Number 185,393.

I claim:

1. In a heating system embodying a furnace, an electrically operated blower device for controlling the combustion of fuel therein, a movable regulator member controlled by the thermal conditions prevailing in the furnace, and switch mechanism for controlling the supply of power to the said blower; the combination with an oscillatable bar of said regulator member; of a liquid containing member carried by said bar; a link pivotally connected with the bar; an arm extending from the switch mechanism and slotted longitudinally and the lower end of said link being movably connected into the slot thereof; and an adjustable stop member movable on said arm to determine the extent of movement of the link end.

2. In a heating system embodying a furnace, an electrically operated blower device for controlling the combustion of fuel therein, and temperature regulator member of said furnace; the combination with an oscillatable bar of said regulator; of a control member rigidly carried thereby and embodying a liquid-containing member divided into two compartments having communication with each other through an upper and a lower opening in one of the compartments; and means for controlling the flow through the lower opening to delay return movement of said regulator bar over its actuating range; a switch member operated by the movement of said bar to control the circuit to the blower device; a link pivotally connected with the bar; and an arm extending from the switch mechanism and slotted longitudinally and the lower end of said link being movably connected into the slot thereof.

In testimony whereof I afiix my signature.

LOUIS HOEDT. 

